New research conducted by University of Oxfords Institute
of Cognitive and Evolutionary Anthropology suggests that exercising
in a group can be more healthy than working out alone.

Researchers studied Oxfords rowing team to come up with
their conclusion.

The crew was divided into teams, each with six members and asked
to work out with identical rowing machines. The only variable
was whether the workouts were done alone, or in teams exercising
together, with the six machines coordinated by the crews
coxswain.

The end of each workout saw the blood-pressure cuff around one
arm of each participant being tightened until he reported pain.
This was done to measure endorphin levels in the brain.

Endorphin is a chemical that not only creates gives a mild high
but also blocks out pain. And it was seen that the rowers
pain threshold was steadily twice as high after exercising in
a group than exercising alone even with the same intensity of
the workouts.

The researchers concluded that group bonding releases more endorphin.

We also suspect that shared goals  ultimate goals,
like winning the big race, and proximate goals, like endeavouring
to row together in synch  are at least part of the trigger,
the Globe and Mail quoted lead author Emma Cohen, as saying.